HYDROACOUSTICS

Hydroacoustics Laboratory

The Hydroacoustics Laboratory gives support to R&D projects and to the acoustic characterization of all kind of underwater equipment.

The laboratory has a troncochonical tank with a depth of 10 meters with a georeferenced positioning system. This tank allows to simulate free field measurements from 3 kHz up to 2 MHz which. This avoids the need to carry out open sea measurements by offering a controlled measurement environment, saving the costs resulting from the deployment of equipment at sea. It also has the equipment required to automate signal generation, data acquisition and signal processing.

The laboratory offers services to characterize analogue and digital underwater electro-acoustic transducers, according to norm IEC60565, in frequencies that range from 3 kHz to 2 MHz as well as sonic frequencies using air acoustics equipment.

The Hydroacoustics Laboratory team also carries out measurements of descriptive parameters of underwater acoustic absorption performance of different materials such as Echo reduction and Insertion Loss.

Underwater noise pollution

Environmental surveillance and assessment of the impact of underwater noise on marine species .

The Marine Strategy Framework Directive 2008/56/EC and the Law 41/2010 for Marine Protection constitute the legal framework in which Spain will base its marine planning in order to achieve the Good Environmental Status.

Good Environmental Status (GES) is determined according to 11 Descriptors. Descriptor 11 refers to underwater noise, which according to annex 1 of the MSFD is: “Introduction of energy, including underwater noise, is at levels that do not adversely affect the marine environment”. CTN is the technology partner in the field of underwater noise pollution of the main national actors on marine environment: the Spanish Ministry of Agriculture, Food and Environment, the Spanish General Directorate of Coastal and Marine Environment, the Spanish Institute of Oceanography (IEO).

Anechoic materials and tanks for Underwater Noise mitigation

CTN has developed and registered through a patent an elastomer composition with applications in underwater noise mitigation (P201232056). The material, which absorbs underwater waves in frequencies of 50 kHz or higher, allows to carry out any kind of tests into acoustic devices (hydrophones, acoustic waves, sonars, etc) in controlled environments with a decrease of early reflections in direct sound close to 30 dB for frequencies of 50kHz or higher.